1. Technical Field
This invention relates in general to telecommunications and, more particularly, to optical transport networks.
2. Description of the Related Art
DWDM (Dense Wavelength Division Multiplexing) allows a single optical fiber to carry voice and data traffic over a large number of discrete channels (each channel operating on a different wavelength). Because of the efficiency advantages of DWDM, telecommunication service providers are building new networks and replacing old networks with optical systems using this technology.
UNI 1.0 was proposed by OIF (Optical Internetworking Forum) to enable client to dynamically establish optical connections using signaling procedures compatible with Generalized MPLS (GMPLS) signaling. Additionally, UNI 1.0 provides a neighbor discovery mechanism to permit equipment on both ends of a fiber link to identify each other; this allows management systems to build interconnection maps automatically. A service discovery mechanism enables clients to determine the services that are available from the optical network.
UNI 2.0 requires networks to support multiple-homing route diversification. Multiple-homing route diversification provides for the establishment of different paths between ingress and egress UNI clients (“UNI-C's). However, there is no established means of creating a diversified path from an existing path.
One current proposal involves passing diversification information, such as SRLG (shared risk link group), node and link information from the ingress network element (UNI-N) to the ingress client. This proposal, however, involves sending important information regarding the configuration of the network to entities outside of the network. From a security standpoint, transport network providers are against sending network information to external entities.
Accordingly, a need has arisen for a method and apparatus to provide multiple-homing route diversification without divulging proprietary information to external entities.